Field
This disclosure relates generally to semiconductor devices, and more specifically, to diodes having multiple junctions.
Related Art
Integrated circuits (ICs) and other electronic apparatus often include arrangements of interconnected field effect transistor (FET) devices, also called metal-oxide-semiconductor field effect transistors (MOSFETs), or simply MOS transistors or devices. A control voltage applied to a gate electrode of the FET device controls the flow of current through a controllable conductive channel between source and drain electrodes.
Power transistor devices are designed to be tolerant of the high currents and voltages that are present in power applications such as motion control, air bag deployment, and automotive fuel injector drivers. One type of power transistor is a laterally diffused metal-oxide-semiconductor (LDMOS) transistor. Power transistor devices may have a number of features customized to prevent breakdown resulting from the high electric fields arising from such high voltages. Power transistor devices are often combined in ICs with low voltage FET transistor devices. The low voltage devices provide logic or analog functionality to support the operation of the high voltage devices.
The fabrication process flow is thus configured with a considerable number of dopant implantation and other procedures directed to creating features specific to the high voltage FET devices and the low voltage FET devices. The procedures may be highly customized to optimize the features of the high and low voltage devices. The customization of the procedures may not be conducive to fabricating conventional designs of other semiconductor devices, such as diodes, in the same process flow. Diodes are electronic components that are also utilized to control current flow, depending on how the diode is biased. The customization of the procedures may also result in expenses that leave little, if any, resources for implementing procedures customized for fabricating such other semiconductor devices.
The present invention is illustrated by way of example and is not limited by the accompanying figures, in which like references indicate similar elements, unless otherwise noted. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale.